Naturalist and filmmaker Eric Ashby, who has died aged 85, began his remarkable life's work filming Britain's native wildlife as a 16-year-old, having spent his pocket money on an Ensign 16mm cine camera. In the early 1960s, his films brought delight and wonder to viewers of the BBC's popular series Look, which was presented by Sir Peter Scott. So impressed was Scott by Ashby's remarkably intimate close-ups of wild forest animals that he dubbed him the Silent Watcher.

Ashby was shy and retiring, ideal qualities for the unobtrusive observation of deer, foxes and badgers of the New Forest, Hampshire, where he lived. He wanted, through his camera, to entertain and inform. Christopher Parsons, his producer at the BBC's Natural History Unit in Bristol (obituary, November 14 2002), nurtured Ashby's talent, certain that his revelations would fascinate millions who might otherwise have no interest in wildlife.

Eric Ashby was born on the west coast of Cumberland, but the family moved to Southsea, Hampshire, where he went to school. When he was 12, Ashby watched the great traveller and pioneer of animal photography Cherry Kearton present a public showing of his films about Africa at the South Parade Pier. Although amused and thrilled by the showman, Ashby detected that not all the animals were behaving naturally, which to his mind was what nature films should really represent.

From that moment, he set himself the high standards of still photography and filmmaking in the wild that became his hallmark. Technical innovations, such as soundproofing his clockwork camera, together with knowledge of the animals themselves, enabled him to film badgers foraging in daylight for the first time. He refused to film with tame or habituated animals, as some of his contemporaries were doing. If it needed 90 separate visits to see one wild animal going through a badger-gate in a fence, then that was what Ashby gave it.

In the tightly budgeted world of television, his principles made his method uneconomic. But money was never his motivation, and his filming was always encouraged, even if he did need four years of his own time to shoot enough sequences for his first 45-minute film, The Unknown Forest, which was shown by the BBC in 1961. A unique portrait of real animal lives, it was a huge success. Other films followed, among them A Hare's Life, A Forest Diary and The Private Life Of The Fox. There was also a biographical piece called The Silent Watcher.

As particular about sound as he was about pictures, the story goes that he first met his wife Eileen in the forest. An enthusiastic amateur sound recordist, she was recording on one side of a large oak tree while he was quietly filming on the other.

An oak was to figure in their later life. The BBC Natural History Unit's study of an oak tree, The Major, was the first wildlife film in colour. Ashby's task was to film the small mammals and birds, in particular, a memorable sequence of a blue jay burying acorns. Shown first in monochrome, the film was not transmitted in colour until 1967, when the colour service began.

Ashby's first pictures, with a new plate camera, had been published in the Boy's Own paper together with his article on bird photography as a hobby for boys. By 1937 he knew how to film a whole sequence of fox cubs at play. Only the second world war diverted him from his passion, and he concentrated on vital farming with his brother Rex in Devon. Once he had moved back to the New Forest he never left the area, and he shared his love of it with the world.

In 1982 he was caught up for a time in an unpleasant conflict with his local hunt, which was prompted by the unexplained killing of deer in his garden. Then, much later, incursions by hounds on to his land caused the badgers he was filming for the BBC to desert the sett. The film had to be cancelled and Ashby won a case against the hunt, which retaliated by effectively fencing off Badger Cottage "to keep their hounds off his land". As a result few wild animals could enter the garden and the locals referred to it as "Stalag Ashby". Eric Ashby was a quiet man, but he was always ready to fight for what he believed in.

In recent years, Badger Cottage became a haven for some 30 wild foxes from rescue centres. Visitors from around the world came to see how Eric and Eileen cared for them. They even raised a cub called Tiger, and told his story in a book: My Life With Foxes (2000).

When I began work with the Natural History Unit in 1962, the name Eric Ashby was already spoken in reverential tones. Few had ever seen him, and because he was shy of strangers we were discouraged from visiting him. I did see him in 1997, at the BBC in Bristol, when he attended the Natural History Unit's 40th birthday celebration. Sadly, few people seemed to know who he was, and he slipped away early, vanishing silently to his cottage in the forest, where he was truly at home.

Eileen survives him.

· Eric Ashby, wildlife photographer and filmmaker, born January 19 1918; died February 6 2003